With continuous increase of the integration degree of semiconductor devices, the critical dimension of semiconductor devices decreases continuously. However, problems arise. For example, the surface resistance and the contact resistance in the source/drain regions of the devices may increase, and thus the response speed of the devices may decrease and the signals may be delayed. Therefore, interconnection structure with a low resistance becomes a key factor for fabricating highly integrated semiconductor devices.
To reduce the contact resistance in the source/drain regions of the devices, a metal silicide fabrication method may be introduced. The metal silicide may have a relatively low resistivity, and thus the contact resistance at the source/drain electrodes may be significantly reduced. Specifically, metal silicide, self-aligned metal silicide, as well as the corresponding formation processes have been widely used to reduce the surface resistance and the contact resistance of the source electrodes and the drain electrodes, and thus may reduce the resistance-capacitation delay (RC delay).
According to existing self-aligned metal silicide technology, SiNix is usually used to form the metal silicide. Specifically, the metal silicide formed using the SiNix may demonstrate advanced properties including low contact resistance, low silicon consumption, etc. and may also be able to easily reach a relatively narrow line width. Therefore, SiNix is regarded as an ideal metal silicide.
As semiconductor devices are developed to switch from planar devices to fin field-effect transistor (Fin-FET) devices, the contact resistance in Fin-FET devices formed by existing metal silicide methods may not meet the device performance requirements. Therefore, new methods for fabricating Fin-FET devices are highly demanded to reduce the contact resistance in the formed Fin-FET devices, and thus improve the operation speed of the Fin-FET devices. The disclosed Fin-FET devices and fabrication methods thereof are directed to solve one or more problems set forth above and other problems in the art.